Prior to the present invention, connecting synchronous masters to each other was very awkward. Generally this task was accomplished by connecting the first master to a slave unit which in turn was connected to an elastic buffer. The elastic buffer was then connected to a second slave unit which was connected to the second master (here, the second master would be a Data Adapter). With this arrangement, some kind of "flow" control was required because inevitably, one of the masters transmitted at a slightly higher rate.
Because of the nature of the Data Adapter, it is synchronized to the Central Office (CO) and is generally a master for synchronous data. But limiting the Data Adapter to only external slave devices is to restrictive.
It therefore becomes the object of the present invention to provide an apparatus which allows an external master device to be connected to a Data Adapter.